Dental impression method with photocuring of impression material in light transmissive tray

Abstract

Disclosed in the present application is a method of curing a dental impression material by passing actinic light through a tray while the tray is in contact with the impression making composition, a new dental impression composition that is polymerizable by having an initiator activated by actinic light within the visible light range of 360 to 600 nanometers, a new composition of matter that is a compound having at least two terminal acrylate unsaturations and an organosilicone containing backbone and a new method of forming dental prosthetics by directly forming against the soft tissue of the oral cavity and then setting with visible light curing.

It is claimed: 
     
       1. A method of forming a dental impression in the oral cavity comprising (a) engaging composition that is flowable and at least substantially free of memory with a surface in the oral cavity that is to have its dental impression taken, including forcing a tray of said composition toward the surface until some of said composition flows to assure good engagement of said composition with the surface; and   (b) maintaining said tray in contact with said composition and passing actinic light through at least an integral part of said tray photopolymerizing said composition to a degree that said composition assumes a permanent elastomeric remembered form.   
     
     
       2. The method of claim 1 wherein said actinic light, except for ambient light, is substantially limited to the visible light spectrum of about 360 to about 600 nanometers. 
     
     
       3. The method of claim 1 wherein said tray passes actinic light through the majority of its mass to said composition. 
     
     
       4. The method of claim 1 wherein said composition is substantially stable against assuming a permanent remembered form when stored actinic light free. 
     
     
       5. The method of claim 1 wherein said composition is substantially non-absorbing to tooth enamel when changed from said flowable to said remembered form by exposure to actinic light and in said remembered form being deformable in response to pressure applied by the human hand to pull of of teeth retaining the remembered shape of the teeth in detail. 
     
     
       6. The method of claim 1 wherein said composition is non-toxic in use in the oral cavity, is stable in storage for at least one (1) month as a one-component composition when actinic light free, and assumes a permanent elastomeric memory when exposed to light filtered to limited wavelengths within the visible light range for one (1) minute to a depth of one (1) inch. 
     
     
       7. The method of claim 1 wherein said composition comprises a polysiloxane. 
     
     
       8. The method of claim 7 wherein said composition is photopolymerized at least in part through photo-cross-linking of two pendent C-C-double bonds. 
     
     
       9. The method of claim 8 wherein said polysiloxane comprises organosiloxane with two pendent C-C-double bonds prior to photopolymerizing and said composition prior to said photopolymerizing is substantially free of sites for condensation polymerization. 
     
     
       10. The method of forming a dental impression of claim 11 wherein said composition comprises a compound that has at least two acryl ethylenic unsaturated pendant groups that polymerize through free radical reaction, said compound having the general formula ##STR4## R 1  =H, alkyl, sub alkyl, F, CN, aryl, sub aryl R 2  =alkylene, sub alkylene, arylene, sub arylene B=An organic radical substituent;   n=1 or more; and   it being further understood that the backbone of the compound of the general formula may be a homopolymer of A or B or an alternate block or random block copolymer of A or B and A and/or B may be the same or different for each n within the compound.   
     
     
       11. The method of claim 10 wherein said dental impression composition includes at least two polyorganosiloxane compounds, a first polyorganosiloxane containing not more than 3 polymerizable acryl groups, and a second polyorganosiloxane containing at least 3 acryl groups. 
     
     
       12. The method of claim 11 wherein y is 0 and said first and said second polyorganosiloxanes are according to said general formula and x, for the first polyorganosiloxane is 2 to 20,000 and for the second polyorganosiloxane 2 to 10,000. 
     
     
       13. The method of claim 12 wherein said dental impression composition includes at least about 20% by weight, exclusive of filler, of compounds according to said general formula and at least about one half of said 20% is of compounds wherein y=o and said first polyorganosiloxane has the formula ##STR5## R 3  =saturated alkylene, sub alkylene, ary, sub arylene R 3  may be the same or different h=1 to n   and said second polyorganosiloxane has the formula ##STR6## j and m=1 to n k=o to n   u=1 to n   v=o to n   Siloxane radicals with u, k and v exponents can repeat, alternately forming multiple blocks, the blocks can be the same or different powers of u, k and v.